JP2009290756A - Image processing apparatus, image processing method, program for making computer implement the method, and computer-readable recording medium with the program recorded thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent forgery of a document by detecting copy inhibition information or a ground tint pattern area on the document even when magnifying the document with any arbitrary magnifying power. <P>SOLUTION: When a specific dot pattern is detected in a pattern detection device 17, image-embedded information (detecting signal) of the dot pattern is transmitted to a ground tint pattern position storage device 18, and the ground tint pattern position storage device 18 calculates from the received image-embedded information and stores the position of the dot pattern after 50% reduction magnification of read image data (S13). Next, the image data and positional information of the dot pattern are fed back to an image data processing apparatus 2 (S14). The image data processing apparatus 4 specifies the position of the dot pattern on the basis of the positional information of the dot pattern after 50% reduction magnification calculated by the ground tint pattern position storage device 18, paints out the position (S16) and outputs the image data to a plotter 7 (S17). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image processing apparatus, an image processing method and a program for causing a computer to execute the method, and a computer readable recording the program. The present invention relates to a recording medium.

Conventionally, as a security measure to prevent leakage of information such as images printed on a manuscript, operation restrictions are imposed on the device that prints the manuscript itself, or copy prohibition information is formed on the manuscript itself to generate duplicate data Preventing so-called unauthorized copying, which is impossible.
For example, if a predetermined pattern is printed on a document when the document is created and the copy prohibition information is read when the document is copied, the read document image data (input data) is replaced with another image data (fixed value). For example, an apparatus for forming an image as if it was filled is known.

  Also, by adjusting the size of the dots making up the image and the number of dots per predetermined pixel, the background consists of areas that are detected by the reading device and areas that are not detected. In order to prevent forgery of the original document, only one area is read by the reading device and characters and figures (latent images) emerge. Yes.

Of this copy-forgery-inhibited pattern pattern, the area to be detected by the reading device is determined by the number of dots per predetermined pixel and area density of the original image. For example, a predetermined area is used for scaling and copying the original image. When the magnification is reduced, the number of dots per predetermined pixel and the area density may change, and the reading device may not be able to properly detect the region to be detected.
In order to solve this problem, an image that prevents copying from being performed without recognizing the copy-forgery-inhibited pattern is set by setting the original reading magnification to a magnification that can recognize the copy-forgery-inhibited pattern (original reading lower limit scaling factor). A reader is known (see Patent Document 1).

In addition, the number of latent images due to copy prohibition information and copy-forgery-inhibited pattern printed on the original increases and decreases with the size of the original, so when the original size is small, the number of copy prohibition information and latent images is small, There is a possibility that these may be erroneously detected or not detected when read.
On the other hand, in order to prevent the above-described erroneous detection caused by the document size being too small, when the document size is detected in advance when the document is read and the document size is equal to or smaller than the predetermined size, image data is output. An image forming apparatus is known that prevents output in a state where copy prohibition information or a latent image is not detected or in a state where a copy is not detected or is erroneously detected (see Patent Document 2).

  However, since the lower limit scaling factor is automatically set in the image reading apparatus described in Patent Document 1, when copying a document having a copy-forgery-inhibited pattern, copying cannot be performed below the scaling factor. The image forming apparatus described in Document 2 has a problem that the degree of freedom in printing is limited because an original having a predetermined size or less cannot be copied.

In order to solve this problem, that is, in order to be able to read the copy prohibition information formed on the original even if the original is reduced and scaled, the pattern image (copy prohibition information) is made as an image of a plurality of sizes in advance. An image forming apparatus is also known that can detect a pattern image of any size even after scaling (see Patent Document 3).
However, in this image forming apparatus, pattern images of a plurality of sizes must be formed in advance, and magnification copying cannot be performed on a document on which a normal background pattern is already formed.
JP 2006-173909 A JP 2007-166222 A JP 2007-201898 A

  The present invention has been made in view of the above-described conventional problems. The object of the present invention is to provide a copy-prohibited information and a copy-forgery-inhibited pattern even if the original on which the copy-prohibited information and the copy-forgery-inhibited pattern are printed is freely scaled. This is to reliably detect the pattern area and prevent forgery of the document.

The invention of the present application is an image processing apparatus comprising: a document reading device; and a first scaling unit that scales and outputs image data read by the reading device based on a predetermined scaling factor. A detection device for detecting copy prohibition information in the read image data; position information acquisition means for acquiring position information of the copy prohibition information after scaling from the copy prohibition information in the detected image data; And copy prohibition processing means for performing copy prohibition processing at the position of the copy prohibition information of the image data after scaling.
Another invention of the present application includes an image processing method including a reading process for reading an original, and a first scaling process for scaling and outputting image data read in the reading process based on a predetermined scaling ratio. A detection step of detecting copy prohibition information in the read image data, and position information for acquiring position information of the copy prohibition information after scaling from the copy prohibition information in the detected image data And an acquisition step and a copy prohibition processing step of performing a copy prohibition process at the position of the copy prohibition information of the image data after scaling.
Further, according to another invention of the present application, a first reading process of a document image for the purpose of detecting copy prohibition information in the document image, and a document image read in the first reading process are detected in the detection process. From a third scaling step for enlarging and scaling to a possible size, the detection step for detecting copy prohibition information in the image data of the read original image, and copy prohibition information in the detected image data, A position information acquisition step of acquiring position information of the copy prohibition information after the scaling, a second reading step of a document image intended to perform a scaling process on the document image, and the second reading step; A fourth scaling step for scaling the read document image at a predetermined scaling factor; and a copy prohibition processing step for performing a copy prohibition process on the position of the copy prohibition information in the image data after the scaling. It is characterized by that.
Another invention of the present application is a program for executing each step of the image processing method by a computer.
Furthermore, another invention of the present application is a computer-readable recording medium on which the program is recorded.

  According to the present invention, even if an original on which copy prohibition information and a copy-forgery-inhibited pattern pattern are printed is freely reduced and scaled, the copy-prohibition information and the copy-forgery-inhibited pattern pattern area can be detected. The degree of freedom can be improved.

Hereinafter, an image processing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a functional block diagram of an MFP (Multi Function Peripheral) having functions such as a copy function, a scanner function, a printer function, a FAX function, and a document box function as an example of an image processing apparatus according to the present embodiment. is there.

  The MFP includes a reading device 1 such as a scanner that reads a document image, an image data processing device 2 that performs predetermined processing on digital image data read by the reading device 1, and the image data processing device 2 performs the above processing halfway. For example, a pattern detection device 17 that detects a specific dot pattern indicating copy prohibition information or the like of the performed image data, and image data processing that performs copy prohibition processing such as painting on the image data processed by the image data processing device 2 A device 4, an HDD (Hard Disc Drive) 5 which is a nonvolatile mass storage medium for storing electronic data, a CPU (Central Processing Unit) 6 such as a microprocessor for controlling the entire MFP, and necessary image data Is a data bus control device that exchanges various data such as control commands and bridges between multiple bus standards A bus control device 3, a memory 7 that is a volatile storage medium that temporarily stores programs executed by the CPU 6 and intermediate processing data, and a plotter that outputs image data to transfer paper in an electrophotographic manner. From a device 9, a plotter I / F (interface) device 8 for outputting image data to the plotter device 9, and a dot pattern (copying prohibition information) of a background pattern which is image embedding information described later detected by the pattern detection device 17. A copy-forgery-inhibited pattern position information storage device 18 that is a position information acquisition unit that calculates (acquires) the position of the copy-forgery-inhibited pattern in the original image data and stores it, and an operation display device 10 that is an interface between the user (user) and the apparatus. A line I / F device 11 for connecting the bus and the telephone line, and an external device such as a PC (personal computer). An external I / F unit 12 to continue, a ROM (Read Only Memory) 14 storing a program that CPU6 is executed, and bridging between the device and the ROM 14 S. B. (South Bridge) 13.

The reading device 1 includes a line sensor including a CCD (Charge Coupled Device) photoelectric conversion element, an A / D (Analog / Digital) converter, and a drive circuit thereof, and is obtained by scanning a document set on the MFP. RGB (Red Green Blue) 8-bit digital image data is generated from the grayscale image of the document and output to the image data processing device 2. Further, the reading device 1 can read a document image that has been enlarged or reduced by an arbitrary mechanical scaling unit.
The image data processing device 2 performs predetermined processing for unifying brightness, sharpness, and the like, which will be described later, on the digital image data received from the reading device 1 to predetermined characteristics, and is acquired from the pattern detection device 17. The detected signal is output to the image data processing device 4 through the bus control device 3 together with the digital image data subjected to the predetermined processing. Further, the image data processing device 2 includes a first scaling unit that can electrically scale the size of the image data based on a predetermined scaling factor.

For example, the bus control device 3 is connected to the image data processing devices 2 and 4 and the CPU 6 by a PCI-Express bus, and is connected to the HDD 5 by an ATA (AT Attachment) bus that is standardized by expanding IDE, and is made into an ASIC. ing.
The image data processing device 4 performs image processing suitable for the output destination designated by the user on the digital image data whose characteristics are unified by the image data processing device 2 and outputs the digital image data. In the present embodiment, the processing content and processing parameters of the image processing of the image data processing device 4 are switched according to image embedding information described later detected by the pattern detection device 17.

The HDD 5 is also used for a desktop personal computer and stores incidental information of digital image data in addition to storing digital image data.
The memory 7 is, for example, a DIMM (Dual Inline Memory Module) used in a PC. In order to reduce the speed difference when bridging between multiple types of bus standards and the processing speed difference of connected components themselves, Temporarily store the data to be processed.

The CPU 6 is integrated with a predetermined function, for example, a connection function with a general-purpose standard I / F and a bus connection function using a crossbar switch in a CPU core unit such as RM11100 (trade name) manufactured by PMC. (Integrated) CPU is used.
Since the CPU 6 performs processing at high speed, the system is activated by a boot program stored in the ROM 14 at normal startup, but thereafter, processing is performed by a program developed in the memory 7 accessible at high speed.

The plotter I / F device 8 starts from CMYK (C: cyan, M: magenta, Y: yellow, K: black) transmitted via a general-purpose standard I / F such as PCI-Express integrated in the CPU 6. When the digital image data is received, a bus bridge process for outputting to the dedicated I / F of the plotter device 9 is performed.
When the plotter device 9 receives the digital image data from the plotter I / F device 8, the plotter device 9 outputs the image data to the transfer paper using an electrophotographic process using a laser beam.

S. B. Reference numeral 13 denotes a chip set used for a PC, which is a general-purpose electronic device, which is a general-purpose circuit that bridges a bus used when a CPU system including a PCI-Express and an ISA bridge is mainly constructed. Is.
The operation display device 10 includes, for example, an LCD (Liquid Crystal Display) that displays various states and operation methods of the device, and a key switch for a user to input an instruction, via a PCI-Express bus (general-purpose standard I / F). To connect to the CPU 6.

The line I / F device 11 is connected to the FAX 15 via a telephone line, and can transmit / receive various data to / from the FAX 15.
The external I / F device 12 is connected to the PC 16 via a network (Ethernet (registered trademark)), and can transmit / receive various data to / from the PC 16. Further, the user can perform various controls and input / output of image data to / from the MFP via application software and drivers installed on the PC 16.

  When the pattern detection device 17 detects a specific dot pattern from the image data that has been processed halfway by the image data processing device 2, it extracts the image embedding information represented by the dot pattern from the image data, A value corresponding to the image embedding information is transmitted to the image data processing device 2. When a specific dot pattern is not detected, a value “0” is transmitted to the image data processing device 2.

Next, the processing of the image data processing devices 2 and 4 shown in FIG. 1 when scaling the read image will be described.
FIG. 2 is a diagram illustrating the processing of the image data processing device 2 during the scaling process.
As mentioned above, MFP has various functions such as copy function, scanner function, printer function, FAX function, document box function, etc., but all of them operate almost the same except for output means. Examples will be described.

As shown in the figure, first, when the RGB image data read from the reading device 1 is output to the image data processing device 2, the image data processing device 2 performs γ (gamma) conversion, thereby increasing the brightness of the RGB image data. For example, the brightness of the RGB image data is γ-converted into a linearity value.
Next, the sharpness of the RGB image data with uniform brightness is standardized to a predetermined characteristic, that is, for example, when a reference chart is scanned, a predetermined MTF characteristic value is obtained for each number of lines. Convert to (filter processing).

Subsequently, the colors of the RGB image data are unified to a predetermined characteristic, that is, color conversion is performed so that, for example, the color space becomes an Adobe-RGB color space.
Further, the size (resolution) of the RGB image data is unified to a predetermined characteristic, that is, for example, scaling processing is performed to 600 dpi (dot per inch).
As described above, RGB image data in which brightness, sharpness, color, and size are standardized to predetermined characteristics are transmitted to the bus control device 3 via the PCI-Express bus.

FIG. 3 is a diagram for explaining processing of the image data processing device 4.
The image data processing device 4 has different processing operations depending on the type of detection signal received from the pattern detection device 17 shown in FIG.
As shown in the figure, when the detection signal received from the pattern detection device 17 is “0”, that is, when a specific dot pattern is not detected from the RGB image data, the image data processing device 4 first sharpens the RGB image data. In order to improve the reproducibility when output by the plotter device 9 shown in FIG. That is, for example, in a character mode for printing a document, a sharpening process is performed to clarify the character, and in a photo mode for printing a photographic image, a smoothing process is performed to smoothly express gradation. Thus, sharpening and smoothing processing according to a desired mode is performed.

Next, the image data processing device 4 performs color conversion on the RGB image data (RGB 8-bit data) into CMYK 8-bit data that is a color space suitable for the plotter device 9 shown in FIG. At this time, the saturation is similarly adjusted according to the mode information desired by the user (character mode, photo mode, etc.).
The color-converted CMYK image data is subjected to size (resolution) conversion (scaling process) according to the reproduction performance of the plotter device 9 shown in FIG. This scaling process has a simple scaling function.

Subsequently, the image data processing device 4 performs the scaling process on the CMYK image data according to the gradation processing capability of the plotter device 9 shown in FIG. Tone number conversion processing (gradation processing) is performed using a certain error diffusion method.
If a specific dot pattern is not detected from the image data, the paint processing is not performed and the data is transmitted to the bus control device 3 shown in FIG.

On the other hand, when the detection signal received from the pattern detection device 17 is not “0” but the image data processing device 4 has a value corresponding to the image embedding information represented by the dot pattern as described above (that is, When the pattern detection device 17 detects a specific dot pattern from the RGB image data), the above-described filter processing, color conversion, scaling processing, and gradation processing are performed on the RGB image data, and the CPU 6 shown in FIG. Based on the tint block position information received from the tint block position storage device 18, the pixels that match the unreadable area on the image data (the area where the specific dot pattern exists (see FIG. 5 described later)) are filled (filled). processing).
In this way, when a specific dot pattern is detected, the area can be painted to prevent forgery of the document.
In the filling process here, the unreadable area may be filled in black or white, or dot-like data may be added.

Next, in the present embodiment, a processing flow of each apparatus when executing a normal copy process, that is, a copy process not involving a scaling process, will be described.
In FIG. 1, the user first sets a document on the reading device 1, and inputs to the operation display device 10 settings such as a mode desired by the user and an instruction to start copying.
The operation display device 10 converts information input from the user into control command data inside the device. The converted control command data is notified (transmitted) to the CPU 6 via the PCI-Express bus.

The CPU 6 reads and executes a copy operation process program from the ROM 14 in accordance with control command data instructing the start of copying, and sequentially performs settings and operations necessary for the copy operation.
That is, first, the reading apparatus 1 scans a document, and the obtained 8-bit RGB digital image data is processed by the image data processing apparatus 2 to unify the predetermined characteristics (see FIG. 2). Is given.

Data in the middle of the processing is taken into the pattern detection device 17 to detect whether there is a specific dot pattern.
The pattern detection device 17 transmits “0” when the specific dot pattern is not detected, and transmits the value of the image embedding information as the detection signal to the image data processing device 2 when detected. Transmits image data standardized to predetermined characteristics and the detection signal to the bus control device 3.

When the bus control device 3 receives the RGB image data and the detection signal from the image data processing device 2, the bus control device 3 stores the RGB image data and the detection signal in the memory 7 via the CPU 6.
The RGB image data stored in the memory 7 is transmitted to the image data processing device 4 via the CPU 6 and the bus control device 3. At that time, the CPU 6 changes the value of the register of the image data processing device 4 according to the value of the detection signal (image embedding information).

As described above, the image data processing device 4 converts the received RGB image data into CMYK image data for plotter output, and outputs it to the bus control device 3. The processing contents and processing parameters of the image data processing device 4 are switched by a detection signal from the pattern detection device 17.
When the MFP performs a FAX operation, the image data processing device 4 converts the received RGB image data into monochrome binary image data. During the scanner operation, monochrome image data, gray scale data, RGB multi-value data, and the like are displayed. Convert to image data. That is, the only difference between the copy operation, the FAX operation, and the scanner operation is the characteristics and output method of the image data to be converted by the image data processing apparatus 4, and the basic processing flow is the same.

  When receiving the CMYK image data from the image data processing device 4, the bus control device 3 accumulates it in the memory 7 via the CPU 6. The CMYK image data stored in the memory 7 is transmitted to the plotter device 9 via the CPU 6 and the plotter I / F device 8. The plotter device 9 outputs the received CMYK image data to transfer paper, and generates a copy of the document.

(Example 1)
In the embodiment described above, a case will be described in which a reduction / magnification process is performed so that a background pattern attached to a document cannot be read.
FIG. 4 is a functional block diagram of the MFP for explaining an example of the flow of scaling processing according to the present embodiment.
It is assumed that the MFP (pattern detection device 17) in the first embodiment described below cannot recognize (detect) a copy-forgery-inhibited pattern (dot pattern) of a document that has been scaled at a scaling ratio of 50%.

When the user designates a zoom ratio of 50% from the operation display device 10, first, the reading device 1 scans an original with a mechanical zoom ratio of 100% (S11). That is, the reading device 1 is a mechanical scaling unit (corresponding to a second scaling unit) that enlarges and scales the read original image in advance so that the read image data can be detected by the pattern detection device 17. Note that the “second scaling unit” includes an electrical scaling unit as will be described later (herein, these scaling units are used as generic terms).
Next, before performing the scaling process on the image data of the scanned document, the pattern detection device 17 detects a specific dot pattern (S12).
When the pattern detection device 17 detects a specific dot pattern, the dot pattern image embedding information (detection signal) is transmitted to the tint block position storage device 18 via the bus control device 3.
The tint block position storage device 18 calculates the position of the dot pattern after 50% reduction / magnification of the read image data from the received image embedding information and stores it (S13).

Next, the image data and the position information of the dot pattern are fed back to the image data processing apparatus 2 (S14).
The image data processing device 2 as the first scaling means performs 50% electrical reduction / magnification on the fed-back image data (S15), and the image data is sent to the image data processing device via the bus control device 3. 4 to send.
The image data processing device 4 identifies the position of the dot pattern based on the position information of the dot pattern after the 50% reduction / scaling calculated by the tint block position storage device 18, and paints the position (S16), thereby plotting the plotter device 7 (S17).

  In step S11, in the present embodiment, the magnification is mechanically changed by the reading device 1. However, after the document is read, the image data processing device 2 (this is the second scaling means of the present invention). The pattern detection device 17 may detect a specific dot pattern in the image data by electrically enlarging and scaling the image data.

5 to 8 are diagrams for explaining a method of calculating the dot pattern position of the image data after scaling in the tint block position storage device 18 in step S13. FIG. 5 shows the original image of the original, and FIG. FIG. 7 shows the position (area) of the dot pattern of the original image of the original, FIG. 7 shows the position of the dot pattern of the original after scaling, and FIG. 8 shows the printed matter finally output.
In FIG. 5, the inner area of the frame of the document indicates the area where the dot pattern is formed (area 1, area 2, area 3 described later).

First, the tint block position storage device 18 detects an area where a dot pattern is formed, and performs classification for each area where the dot pattern is formed, as shown in FIG. The top left vertex of the image data in the figure is defined as the coordinate (0, 0) of the reference point, and the coordinate of the vertex at the diagonal position of the image data with respect to the reference point is defined as (X1, Y1). The coordinates of the position closest to the reference point (hereinafter referred to as the minimum coordinate) and the coordinates of the position farthest (hereinafter referred to as the maximum coordinate) are calculated, and the position information of each of these areas is acquired.
As shown in the figure, the minimum coordinates of the area 1 are (X2, Y2), the maximum coordinates are (X3, Y3), the minimum coordinates of the area 2 are (X4, Y4), the maximum coordinates are (X5, Y5), The minimum coordinate is (X6, Y6), and the maximum coordinate is (X7, Y7).

Thereafter, as shown in FIG. 7, the position and size (position information) of the area after 50% reduction / magnification is calculated and stored (acquired). Here, (X′n, Y′n) = 0.5 * (Xn, Yn) is established.
The tint block position storage device 18 feeds back the acquired position information to the image data processing device 2. Thus, the final output document is painted by the image data processing device 4 at positions corresponding to the respective areas before scaling (see FIG. 8). In other words, the image data processing device 4 serves as a copy prohibition processing means for performing a copy prohibition process at the position of the dot pattern after scaling.

  As described above, the position information of the dot pattern area of the original document after scaling is calculated from the position information of the dot pattern area of the original document before scaling, and based on the calculated position information (feedback) ) Since the original after reduction scaling is painted, an area where no dot pattern exists regardless of the reduction scaling ratio can be output as usual, and the area of the dot pattern can be filled to prevent forgery of the original.

(Example 2)
FIG. 9 is a functional block diagram of the MFP for explaining another example of the flow of the scaling process according to the present embodiment.
Note that the MFP (pattern detection device 17) in the second embodiment described below recognizes (detects) a copy-forgery-inhibited pattern (dot pattern) of a document that has been reduced and scaled at a scaling ratio of 50%, as in the first embodiment. It shall not be possible.

When the user designates a zoom ratio of 50% from the operation display device 10, the reading apparatus 1 scans a document with a mechanical zoom ratio of 50% (S21). Here, the reading apparatus 1 includes a mechanical scaling unit (third scaling unit) that mechanically scales down a read document image in advance.
Next, the image data processing device 2, which is the first scaling unit, electrically enlarges / reduces the image data scaled down to 50% to 200% (S22), and the pattern detection device 17 performs a specific scaling. A dot pattern is detected (S23). The dot pattern image embedding information is transmitted to the tint block position storage device 18.
The copy-forgery-inhibited pattern position storage device 18 calculates the position of the dot pattern after reduction scaling of the image data from the received embedded information by the calculation method described with reference to FIGS. 5 to 8 and stores it (S24).

  The image data and the position information of the dot pattern are fed back to the image data processing device 2 (S25). The image data processing device 2 performs 50% electrical reduction / scaling on the fed back image data (S26), and transmits the image data to the image data processing device 4 via the bus control device 3. The image data processing device 4 specifies the position of the dot pattern after the reduction / magnification based on the position information of the dot pattern calculated by the tint block position storage device 18, paints the position (S 27), and the plotter device 7 Output (S28).

In the second embodiment described above, at the time of zooming, the smaller the zooming ratio at mechanical zooming, the faster the carriage moves and the less time is required, so the mechanical scaling is 50%. The embodiment is more productive than the first embodiment. On the other hand, during zooming, since the movement of the carriage is slow, productivity is worse than that of the first embodiment.
Also, regarding the printed image quality, mechanical scaling and electrical scaling are compared with those in Example 1 in which only electrical scaling except for 100% mechanical scaling is performed regardless of reduction or enlargement. In this embodiment, both of which are doubled, the image quality is poor.

In step S21, mechanical scaling is performed at a scaling ratio of 50%. However, it is sufficient that the carriage moves faster than when the scaling ratio is 100%. Not exclusively.
In step S22, electrical scaling is performed at a scaling ratio of 200%. The size of the image data after the electrical scaling is set to a size that allows the pattern detection device 17 to detect a dot pattern on the image data. It only needs to be scaled and is not necessarily limited to this scaling factor.

(Example 3)
FIG. 10 is a functional block diagram of the MFP for explaining another example of the flow of the scaling process according to the present embodiment.
Note that the MFP (pattern detection device 17) in the third embodiment described below recognizes (detects) a copy-forgery-inhibited pattern (dot pattern) of a document that has been scaled down at a scaling ratio of 50%, as in the first and second embodiments. ).

When the user designates a magnification ratio of 50% from the operation display device 10, the reading apparatus 1 performs prescanning (first reading step), which is a document reading at a mechanical magnification ratio of 100% for the purpose of detecting a dot pattern. Then, based on the image data obtained by this pre-scanning, the pattern detection device 17 detects a specific dot pattern (S32).
When a specific dot pattern is detected by the pattern detection device 17, the dot pattern image embedding information is transmitted to the tint block position storage device 18 via the bus control device 3.
The tint block position storage device 18 calculates the position of the dot pattern after scaling of the image data read from the received embedded information by the calculation method described with reference to FIGS. 5 to 8 and stores it (S33).

Next, the image data and the position information of the dot pattern are fed back to the image data processing device 2 (S34).
Subsequently, the reading device 1 scans the document with a mechanical scaling factor of 50% (second reading step) (second reading step) for the purpose of performing a scaling process on the read image data and outputting it (second reading process) S35), the position of the dot pattern is specified based on the position information of the dot pattern detected by the tint block position storage device 18, the portion is painted by the image data processing device 4 (S36), and output by the plotter device 7 (S37).

  As described above, the position information of the dot pattern of the document is acquired in advance by pre-scanning, so that when the document is read again, enlargement scaling of the image data is performed to acquire the position information of the dot pattern. Without performing the above, it is possible to perform a copy prohibition process (filling process) by changing the magnification at a user-specified magnification.

It should be noted that the present embodiment in which the scanning operation is performed twice is less productive at the time of reduction and enlargement / magnification than the first and second embodiments.
However, with respect to the image quality to be printed, only mechanical scaling is performed as compared with the first and second embodiments in which electric scaling is performed regardless of reduction or enlargement scaling. The image quality is good.

Example 4
In the fourth embodiment, the image data processing device 2 shown in FIGS. 4 and 9 is used in order to improve the reproducibility of the portion where the background pattern of the image data does not exist (the portion other than the dot pattern) in the first and second embodiments. It is possible to switch the process in the electric zooming.
For example, when the image output condition of the MFP is a photographic original mode that is often used for images that change smoothly in general, convolution interpolation is suitable as a method of electrical scaling.
On the other hand, in a character document mode that is generally used for images that change sharply, simple thinning is suitable as an electrical scaling method.
That is, when one of a plurality of image output conditions such as a photo original mode and a character original mode is selected and a copy instruction is given by the user, the CPU 6 performs electrical scaling suitable for the image output conditions. The image data processing device 2 is controlled to switch the processing method for electrical scaling so that scaling is performed by the method.

As a result, according to the specified image output conditions, the method of changing the electric magnification is changed and the image is output, so that image data suitable for each image output condition is output and the image data is reproduced. Can be improved.
In addition to the switching by the above mode, the method of electrical scaling may be switched by an application such as a FAX or a scanner.

(Example 5)
In the fifth embodiment, the copy-forgery-inhibited pattern cannot be recognized at the user's designated scaling factor, and the copy-forgery-inhibited pattern can be recognized at a scaling factor that is an integral multiple of the designated scaling factor. In addition, it is assumed that the MFP (pattern detection device 17) cannot recognize a background pattern at a scaling factor of 33%, but can recognize a background pattern at a scaling factor of 66%, which is an integral multiple thereof.
Similarly, also in the first to third embodiments described above, the zoom ratio of the mechanical scaling at the time of document reading (prescanning in the case of the third embodiment) is set to 100%, which is an integer multiple of the user-specified scaling 50%. By doing so, the background pattern can be recognized.
In this case, a scaling factor parameter (for example, a coefficient that improves the sharpness (sharpness) of the image, a coefficient that emphasizes characters, a coefficient that smoothes the image, etc.) Can be diverted when scaling down. Therefore, the parameter at the time of the scaling factor of 100% can be used when the image data processing apparatus 2 is electrically reduced and scaled to the scaling factor of 50%.

  This eliminates the need for parameter creation (calculation) when the image data processing device 2 performs electrical scaling, reduces the time required to calculate the parameter, and saves the parameter in the memory for storing the parameter. The burden can be reduced.

(Example 6)
In the sixth embodiment, if the dot pattern of the document cannot be detected when scaling is performed at a scaling ratio designated by the user, a plurality of scaling factors as described in the first to fifth embodiments are considered in consideration of productivity and image quality. Select and execute one of the double processing methods.

FIG. 11 is a flowchart illustrating the scaling process according to the sixth embodiment.
First, an original to be copied is placed on the reading apparatus 1 shown in FIG. 1 (S101), a variable magnification is designated, and a copy start button is pressed to instruct a variable magnification copy start (S102). ).
The reading device 1 of the MFP starts reading (detecting) copy prohibition information (dot pattern) of the document (S103). Here, it is determined whether or not the copy prohibition information (dot pattern) can be read with the user-specified scaling factor (S104). If it can be read (S104, YES), the change is made in the same manner as in the past. Double copying is performed (S105).

In step S104, when the copy prohibition information (dot pattern) cannot be read with the user-specified scaling ratio, one of the scaling processing methods (methods) 1 to n described in the first to fifth embodiments is used. Is selected (S106). That is, in this embodiment, n = 5 in the drawing.
Copy prohibition information (dot pattern) is read by the selected scaling process method (method) (S107, S108 or S109), and copying is performed (S110).

Whether or not the copy prohibition information (dot pattern) can be read in step S104 depends on the reading performance of the pattern detection device 17.
In step S106, the scaling process method may be selected, for example, by the user selecting an arbitrary method from the operation display device 10 shown in FIG. 1, or the image output condition set by the user. May be automatically selected based on productivity and / or image quality.

  In order to execute image processing such as the scaling processing described with reference to FIGS. 2 to 11, a computer (image processing apparatus) is caused to read a program describing the procedure of the above processing. The computer program is recorded on a known computer-readable recording medium such as an HDD (hard disk), a CD (compact disk), an FD (flexible disk), or an MO (magneto-optical disk) and installed in the computer. Can do.

FIG. 2 is a functional block diagram of an MFP that is an example of an image processing apparatus according to the present embodiment. It is a figure explaining the process of the image data processing apparatus at the time of a scaling process. It is a figure explaining the process of the image data processing apparatus at the time of a scaling process. FIG. 10 is a diagram illustrating an example of a flow of a scaling process in copying performed by an MFP. It is a figure which shows the original image of a document. It is a figure which shows the position (area | region) of the dot pattern of the original image of a document. It is a figure which shows the dot pattern position of the original document after scaling. It is a figure which shows the printed matter after scaling which is output finally. FIG. 10 is a diagram showing another embodiment of the flow of scaling processing in copying performed by the MFP. FIG. 10 is a diagram illustrating an example of a flow of a scaling process in copying performed by an MFP. FIG. 10 is a flowchart showing a scaling process in Example 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Reading apparatus, 2, 4 ... Image data processing apparatus, 3 ... Bus control apparatus, 5 ... HDD, 6 ... CPU, 7 ... Memory, 8 ... Plotter I / F device, 9 ... plotter device, 10 ... operation display device, 11 ... line I / F device, 12 ... external I / F device, 13 ... S. B. , 14 ... ROM, 15 ... FAX, 16 ... PC, 17 ... pattern detection device, 18 ... tint block position storage device.

Claims (10)

An image processing apparatus comprising: a document reading device; and a first scaling unit that scales and outputs image data read by the reading device based on a predetermined scaling factor,
A detection device for detecting copy prohibition information in the read image data;
Position information acquisition means for acquiring position information of the copy prohibition information after the scaling from the copy prohibition information in the detected image data;
An image processing apparatus, comprising: copy prohibition processing means for performing copy prohibition processing at a position of copy prohibition information of the image data after scaling. The image processing apparatus according to claim 1,
A second scaling means for enlarging and scaling the document image or image data to a size that allows the detection device to detect the copy prohibition information;
The image processing apparatus according to claim 1, wherein the first scaling unit scales down the image data enlarged and scaled by the second scaling unit to a predetermined magnification. The image processing apparatus according to claim 1,
A third scaling unit for reducing and scaling the original image;
The first scaling unit enlarges and scales the image data reduced and scaled by the third scaling unit to a size that allows the detection device to detect copy prohibition information. apparatus. The image processing apparatus according to claim 1,
The second scaling means for enlarging / magnifying the original image or image data to a size capable of detecting the copy prohibition information;
And third scaling means for reducing and scaling the original image,
The detecting device reduces the image data scaled by the second scaling means to a predetermined magnification, or the image data of the original image scaled by the third scaling means is detected by the detection device. An image processing apparatus, comprising: a switching unit that switches an operation of the first scaling unit so that the copy prohibition information is enlarged to a size that can be acquired. An image processing method comprising: a reading process for reading a document; and a first scaling process for scaling and outputting the image data read in the reading process based on a predetermined scaling ratio,
A detection step of detecting copy prohibition information in the read image data;
A position information acquisition step of acquiring position information of the copy prohibition information after the scaling from the copy prohibition information in the detected image data;
A copy prohibition process step of performing a copy prohibition process at a position of the copy prohibition information of the image data after the scaling. The image processing method according to claim 5, wherein
A second scaling step for enlarging and scaling the original image or image data to a size capable of detecting the copy prohibition information;
In the first scaling process, the image data scaled in the second scaling process is reduced and scaled to a predetermined magnification. The image processing method according to claim 5, wherein
A third scaling step for reducing and scaling the read image data;
In the first scaling step, the image data reduced and scaled in the third scaling step is enlarged and scaled to a size capable of detecting copy prohibition information in the detection step. Method. A first reading process of a document image for the purpose of detecting copy prohibition information in the document image;
A third scaling step for enlarging and scaling the document image read in the first reading step to a size that can be detected in the detection step;
The detection step of detecting copy prohibition information in the image data of the read document image;
A position information acquisition step of acquiring position information of the copy prohibition information after the scaling from the copy prohibition information in the detected image data;
A second reading process of a document image for the purpose of scaling the document image;
A fourth scaling step for scaling the original image read in the second reading step at a predetermined scaling factor;
A copy prohibition process step of performing a copy prohibition process at the position of the copy prohibition information of the image data after the scaling.   A program for executing each step of the image processing method according to claim 5 by a computer.   A computer-readable recording medium on which the program according to claim 9 is recorded.

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